title: Effects of norethynodrel on neoplasms in the buccal pouch of the Syrian hamster.
abstract: This study was instituted to determine the effect of a progestin, norethynodrel, on the induction of experimental carcinogens of the hamster cheek pouch. Thirty-six Syrian hamsters were divided into two groups. One group received 2 mg./kg./day of norethynodrel in subcutaneous injections, and the other group received nothing. The right cheek pouches of both groups were painted three times a week with the chemical carcinogen 9,10-dimethyl-1,2-benzanthracene in a 0.05 percent acetone solution. After 9 weeks of painting, the first tumors developed in the hormone-treated hamsters, while none appeared in the control group until after 10 weeks. After 15 weeks, 100 percent of both groups had tumors. The average latent period was 11.8 weeks for the treated group and 12.7 weeks for the control group (p = less than 0.05 percent, Student's test). Norethynodrel significantly decreased the induction time of the neoplasms.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D001835:Body Weight; D002294:Carcinoma, Squamous Cell / Q000209:etiology*; D002610:Cheek / Q000473:pathology; D006224:Cricetinae; D005260:Female; D008647:Mesocricetus; D009062:Mouth Neoplasms / Q000209:etiology*; D009374:Neoplasms, Experimental / Q000209:etiology; D009641:Norethynodrel / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D015127:9,10-Dimethyl-1,2-benzanthracene; D009641:Norethynodrel